A. Category/Name/Source/Contact

(2) Name of Indicator: Pollution Control Efforts –Agriculture, Wastewater, Urban/Suburban Lands and Septic, Air, and Overall

(3) Description of Dataset used to Calculate Percent of Goal Achieved: Chesapeake Bay watershed point source loads and nonpoint source practices, integrated by the Chesapeake Bay Program Phase 4.3 Watershed Model are used to calculate:
• Percent of goal achieved for implementing nitrogen reduction practices to reduce nitrogen 162.5 million lbs from 1985 levels to achieve a 175 million lb/yr cap load, based on long-term average hydrology simulations
• Percent of goal achieved for implementing phosphorus reduction practices to reduce phosphorus 14.36 million lbs from 1985 levels to achieve a 12.8 million lb/yr cap load, based on long-term average hydrology simulations
• Percent of goal achieved for implementing sediment reduction practices to reduce sediment 1.69 million tons from 1985 levels to achieve a 4.15 million ton/yr cap load, based on long-term average hydrology simulations

 For what purpose(s) were the data collected? (e.g., tracking, research, or long-term monitoring.) All of the above
 Which parameters were measured directly? Most of point source flows and effluent concentrations
 Which were obtained by calculation? Point source loads are calculations of measured or estimated effluent flows and concentrations. Nonpoint source practice implementation, from jurisdictional tracking, may involve calculation. The Chesapeake Bay Program Phase 4.3 Watershed Model, used to transform all nonpoint source practices and point source discharges into indicators, is a lumped parameter, physically based mathematical tool simulating physical, chemical, and biological processes in the ecosystem and designed to equitably account for all load sources and assess changes due to management actions .

(4) Source(s) of Data: Annual jurisdictional submissions of both monitored and estimated point source effluent concentrations and flows approved by each jurisdiction as well as nonpoint source practice data tracked by jurisdictions and reported to the Chesapeake Bay Program office.

(10a) What does this indicator tell us?
 Clearer, oxygen-rich waters are the foundation of Chesapeake Bay restoration. The Bay and its tidal rivers receive more nutrients and sediment than a healthy ecosystem can handle. Overall, based on available data, Bay Program scientists project that little more than half of the pollution reduction efforts needed to achieve the pollution control efforts goals have been undertaken since 1985. The goal is to take the actions necessary to remove the Bay and its tidal tributaries from EPA’s list of “impaired waters” by 2010.
 Nitrogen, phosphorus and sediment pollution control efforts are occurring in four major areas or “source sectors”: agriculture, wastewater, urban/suburban and air. Bay jurisdictions have developed river-specific cleanup strategies detailing activities that need to be implemented to reduce the amount of nutrients and sediment delivered to the Bay. Monitoring and tracking data and computer simulations are used to estimate the amount of pollution control efforts implemented in relation to the commitments made by the Bay jurisdictions in their cleanup strategies.

Wastewater:
 Decreases in the amount of nutrients discharged from wastewater treatment plants account for a large portion of the estimated nutrient reductions in the watershed to date.
 As the Chesapeake watershed’s population continues to grow, the volume of waste requiring treatment grows.
 In 2005, Bay jurisdictions began putting into place a new permitting approach that requires hundreds of wastewater treatment plants to install a new generation of nutrient reduction technology equipment.
 Bay jurisdictions are relying on additional reductions from wastewater treatment plants for achieving about 10 percent of their nutrient reduction goals.

Agriculture:
 Farmers employ dozens of conservation practices (also known as best management practices or BMPs) to reduce the amount of pollution reaching local waters and the Bay. In part because they are so cost-effective, the Bay jurisdictions are relying on expanded implementation of practices on agricultural lands, such as planting winter cover crops, for more than half of the remaining nutrient reductions needed to meet water quality restoration goals.
 A variety of practices are being used to reduce nutrients and sediment entering the Bay and its rivers from non-point sources. Nutrient and animal waste management on agricultural lands are particularly effective at reducing nitrogen and phosphorus loads. Conservation-tillage and the use of fencing to keep livestock out of streams are examples of practices being used successfully to reduce sediment loads.

Urban/Suburban Lands and Septic:
 The rapid rate of population growth and related residential and commercial development coupled with ongoing issues associated with accounting for the existing practices has made this pollution source sector the only one in the Bay watershed which continues to still be growing, and thus showing the overall “progress” as negative.
 Stormwater that runs across roads, rooftops and other hardened surfaces carries harmful pollution to local streams and into the Chesapeake Bay. These pollutants include nitrogen, phosphorus, sediment and many chemical contaminants.
 Nitrogen discharged from septic systems is also accounted for in the urban/suburban source sector.
 About one-quarter of the nutrient reductions called for in the jurisdictions’ cleanup strategies are expected to come from efforts to reduce, treat or prevent pollution from urban/suburban lands and septic systems. While improvements have been made in landscape design and stormwater management practices, significant challenges still exist to retrofitting a large portion of existing development called for in jurisdictional plans as well as accounting for existing on-the-ground control practices.
 That aside, to date, it is estimated that the pollution increases associated with land development (e.g. converting farms and forests to urban/suburban developments) have surpassed the gains achieved from improved landscape design and stormwater management practices.

Air:
 Progress in this area is small, but is expected to accelerate dramatically over the next few years as recently-approved air pollution control efforts take effect.
 Pollutants are emitted into the air primarily from vehicles, power plants, agriculture and other industries. These pollutants eventually fall onto water surfaces and the land where they can be washed into local waterways.
 Reducing the release of airborne nitrogen pollution is likely to have the additional benefit of reducing the release of toxic chemicals.
 The Bay jurisdictions are relying upon federal and State air pollution control programs to reduce airborne nitrogen emissions significantly by 2010. This is largely due to mandated air regulations on power plant point emissions of nitrogen oxides (NOx). An estimated reduction of 8 million pounds of nitrogen delivered to the Bay will be achieved by 2010 through Clean Air Interstate Rule (CAIR) reductions.

(11a) Why is it important to report this information?

Trends in implementation of practices and control technologies, and the resultant impacts on loads to the Chesapeake Bay, are useful in understanding trends in water quality and overall ecosystem health. Individual source indicators illustrate the effects of tracked historic implementation of pollutant controls and make comparisons to what is currently forecasted to be needed from the sources to meet restoration goals. Tracking and reporting these impacts is one measure used to clearly assess progress toward meeting Tributary Strategy objectives so effective management actions can be targeted (including addressing funding gaps) that ultimately achieve jurisdictional-adopted water quality standards.

2. Bay Health or Watershed Health indicators only
(7b) What is the long-term trend? (since start of data collection)
(8b) What is the short-term trend? (3 to 5 year trend)
(9b) What is the current status in relation to a goal?

(10b) What is the key story told by this indicator?
(11b) Why is it important to report this information?
(12b) What detail and/or diagnostic indicators are related to this reporting level indicator?
3. Factors Impacting Bay and Watershed Health indicators only
(7c) What is the long-term trend? (since start of data collection)
(8c) What is the short-term trend? (3 to 5 year trend)
(9c) What is the current status?
(10c) What is the key story told by this indicator?
(11c) Why is it important to report this information?
(12c) What detail and/or diagnostic indicators are related to this reporting level indicator?

Wastewater: Point source data can be aggregated to Hydrologic Units (HUC8 and HUC11), counties/cities (FIPS), “state-segments” (the intersection of state boundaries and Phase 4.3 Watershed Model hydrologic segments), jurisdictional portions of major tributaries, major tributaries, jurisdictions, and the Chesapeake Bay watershed as a whole.

Agriculture, Urban/Suburban and Septic, Air:
Nonpoint source practice implementation data is aggregated to “state-segments”, or the intersection of state boundaries and Phase 4.3 Watershed Model hydrologic segments. Further spatial aggregations can be to jurisdictional portions of major tributaries, major tributaries, jurisdictions, and the Chesapeake Bay watershed as a whole.

(18) Are there geographic areas with missing data? If so, where?

Wastewater: Depending on the jurisdiction, effluent flows and concentrations may not be tracked and reported for non-significant facilities.

Agriculture, Urban/Suburban and Septic, Air:
Depending on the jurisdiction, nonpoint source practice implementation data may be over-reported or not be tracked and reported, particularly for voluntary practices.

E. Data Analysis and Interpretation

Please provide appropriate references and location of documentation if hard to find.)

(21) Is the conceptual model used to transform these measurements into an indicator widely accepted as a scientifically sound representation of the phenomenon it indicates? Yes

Wastewater:
The Chesapeake Bay Program Phase 4.3 Watershed Model is the tool used to transform calculated point source discharge loads (generally, from monitored flow and concentration data) to nutrient loads delivered to Chesapeake Bay tidal waters, which the indicator is based on.

Agriculture, Urban/Suburban and Septic, Air:
The Phase 4.3 Watershed Model is also employed to integrate the nonpoint source practice implementation data – submitted by jurisdictions for a host of practices and programs – to changes in delivered nutrient and sediment loads as well as to assimilate the impacts of both point and nonpoint source controls and practices for the Reducing Pollution Summary.

Data and methods used in the Watershed Model as well as the simulation itself and loading outputs are continually under external and internal review. Internal review mostly involves Bay Program subcommittees and their workgroups such as the Nutrient Subcommittee (Tributary Strategy Workgroup, Wastewater Treatment Workgroup, Agricultural Nutrient and Sediment Reduction Workgroup, Urban Stormwater Workgroup, Forestry Workgroup, and Sediment Workgroup); the Modeling Subcommittee; and special task groups established particularly for peer review. Scopes and purposes of these groups and their extensive considerations of the Watershed Model as a planning tool can be found at http://www.chesapeakebay.net/nsc.htm (Nutrient Subcommittee and workgroups) and at http://www.chesapeakebay.net/modsc.htm(Modeling Subcommittee).

The most recent review of the Bay Program’s watershed modeling effort by an independent panel of experts was completed February, 2008. An external panel assembled by the Scientific and Technical Advisory Committee reviewed the Chesapeake Bay Watershed Model assessing (1) work to date, (2) the model's suitability for making management decisions at the Bay Watershed and local scales, and (3) potential enhancements to improve the predictive ability of the next generation of the Chesapeake Bay Watershed Models. A report of the review, with specific recommendations, can be found at the STAC site http://www.chesapeake.org/stac/stacpubs.html

In June, 2005, another review of the Watershed Model addressed the following broad questions: 1) Does the current phase of the model use the most appropriate protocols for simulation of watershed processes and management impacts, based on the current state of the art in the HSPF model development?, and 2) Looking forward to the future refinement of the model, where should the Bay Program look to increase the utility of the watershed model? Details of this review and responses can be found athttp://www.chesapeakebay.net/pubs/subcommittee/mdsc/Watershed_Model_Peer_Review.pdf

A wealth of both general and technical documents about the Chesapeake Bay Program Watershed Model can be found on the Bay Program’s web site. These documents can accessed through the Modeling Subcommittee’s sitehttp://www.chesapeakebay.net/committee_msc_info.aspx under the links “Current Projects” and “Publications”.

The Reducing Pollution indicators have undergone technical and peer review by federal, state and local government and nongovernmental organization partner members of the Bay Program network. Data selection and interpretation and the presentation of the indicator (along with all supporting information and conclusions) are arrived at via consensus of scientists and resource managers of the Bay Program Nutrient Subcommittee, Tributary Strategy Workgroup, Wastewater Treatment Workgroup, and Urban Stormwater Workgroup. Data collection, data analysis and QA/QC is conducted by the custodians of the source data.

How well do the data represent the phenomenon?

The Phase 4.3 Watershed Model is calibrated to long-term monitoring data at 26 calibration sites throughout the basin with edge-of-stream land use calibrations for 9 land categories. For direct comparisons of monitoring and modeled data for the 1985-1994 simulation period, see “CBP Watershed Model – Phase 4.3 Calibration” at http://archive.chesapeakebay.net/temporary/mdsc/index.htm

Of particular significance are the in-stream calibration plots for flows and total nitrogen and total phosphorus loads at the Susquehanna and Potomac fall-lines because of the basins’ considerable impact on dissolved oxygen in the mainstem of the Chesapeake Bay. For an understanding of the Phase 4.3 Watershed Model calibration rules, seehttp://archive.chesapeakebay.net/temporary/mdsc/calibration_0700.pdf

The Watershed Model allows scientists to simulate changes in physical, chemical, and biological processes in a large and complex ecosystem due to changes in human and animal populations, land uses, or pollution management, so that technically sound environmental decisions can be made. Monitoring data provides observations in the past or the present, at discrete times, and at isolated locations while modeling scenarios can be used to represent the environment under different management regimes in different temporal and spatial scales.

The Tributary Strategy goals for the Reducing Pollution indicators represent this “what-if” management regime, providing comparisons among historic and current watershed conditions and a future condition that would restore water quality and living resources in the Chesapeake Bay. So that the comparisons are relevant, reported nonpoint source loads from the Watershed Model are estimates of what would occur in an average hydrology year with a single year’s watershed conditions (i.e., land uses, animal manure and chemical fertilizer inputs, human population, BMPs, septic, and atmospheric deposition). Point source loads reflect measured discharges from tracked waste treatment and industrial facilities, using the model to account for changes in nutrients as the pollutants move downstream.

(22) What is the process by which the raw data is summarized for development and presentation of the indicator?

In developing the Reducing Pollution indicators, comparisons are made within relevant source sectors and among relevant years and goals for nutrient and sediment loads delivered to tidal waters – as estimated by the Chesapeake Bay Program Phase 4.3 Watershed Model. The Watershed Model is employed to integrate the nonpoint source practice implementation data – submitted by jurisdictions for a host of practices and programs – to changes in delivered nutrient and sediment loads. The model also assimilates the impacts of both point and nonpoint source controls and practices for the Reducing Pollution Summary.

The current status of a source indicator is a comparison between 1985-2009 load reductions and 1985-Tributary Strategy load reductions. For the summary Reducing Pollution indicator, the current status is a comparison of all source loads combined between 1985-2009 load reductions and load reductions between 1985 and the Bay Program’s cap load allocations.

1985 is often used as the baseline and 2009 is the most recent annual model assessment of loads to the Bay. Tributary Strategy loads are the model’s assimilation of jurisdictional clean-up plans submitted to the Bay Program office as of 6/22/07, the last date a jurisdictional revision was made. The Tributary Strategies are detailed plans of point and nonpoint source programs, practices and control technologies that, when combined, would meet the cap loads for nitrogen, phosphorus and sediment - as assessed by the Chesapeake Bay Program's Phase 4.3 Watershed Model. The cap load allocations were developed earlier and assigned to each jurisdictions’ portion of the major tributaries of the Chesapeake Bay following a process documented in “Setting and Allocating the Chesapeake Bay Basin Nutrient and Sediment Loads: The Collaborative Process, Technical Tools and Innovative Approaches” at http://www.chesapeakebay.net/content/publications/cbp_19713.pdf There are no caps assigned to sources in the cap load allocations as there is source specificity in the jurisdictional Tributary Strategies.

It is important to note that nonpoint source load estimates depicted by the Watershed Model are based on an average-hydrology year and would not track monitored loads for that particular year. Point source loads reflect measured discharges for each particular year, or the best estimates where data is lacking.

For the Agriculture and Urban/Suburban and Septic indicators, 1986-1999 reported levels of the indicator are linear progressions between the 1985 baseline and the year 2000 when nonpoint source BMP data began to be reported by all watershed jurisdictions. For the Air indicator, data is used for the years 1985, 1996, 2001, and 2005-2007 inclusive. Other years within the air indicator trend period are interpolations of the data.

Wastewater and Agriculture:
The current status of the Wastewater and Agriculture indicators is a comparison between 1985-2009 load reductions and 1985-Tributary Strategy load reductions. The 1985 baseline is that established several years ago after calibration of the Phase 4.3 Watershed Model.

Urban/Suburban and Septic:
The current status of the Urban/Suburban and Septic indicator is a comparison between 1985-2009 load reductions and 1985-Tributary Strategy load reductions where the 1985 scenario has been revised to account for an urban correction factor introduced into the Watershed Model beginning with the 2000 scenario that was not applied to the 1985 baseline. The revised model assessment for 1985 is often used to get better appraisals of changes in loads due to on-the-ground implementation and eliminates the impacts of the urban correction factor (introduced after the model was calibrated) on the model’s results.

Air:
The current status of the Air indicator is a comparison between 1985-2009 nitrogen load reductions to the tidal Bay and 1985-cap load reductions attributed solely to reductions in deposition to the Bay watershed. Overall, there is about a 15 million lb. reduction in nitrogen loads to the Bay planned for air programs in jurisdictional Tributaries and EPA goals to achieve the cap load allocation of 175 million lbs./year.

The benefits in load reductions to the Chesapeake Bay – from reductions in emissions and deposition – are dependent on the land cover the air flux falls on. For the air indicator and most other air impact studies using the model, the land condition is held constant so only changes in loads to the Bay due to changes in deposition are quantified. Model scenarios are run with the same watershed conditions for landuses, manure and chemical fertilizer applications, nonpoint source BMPs, point sources, septic, etc. The baseline watershed or land condition is a scenario where each jurisdictional portion of the major tributaries hits their cap load allocations for nutrients and sediment exactly.

The 1985 baseline for the air indicator is deposition to the Chesapeake Bay watershed of 444.12 million lbs. of nitrogen and a load to tidal waters of the Bay of 189.93 million lbs. This assumes the baseline land condition with atmospheric deposition at levels determined for a 1985 scenario based on monitoring data.

The indicator status for a 2007 scenario sets atmospheric deposition at levels determined from deposition monitoring data employed in the calibration of a revised Watershed Model (Phase 5). A projection of the 1985-2005 calibration deposition data to 2007 yields total nitrogen deposition to the Bay watershed of 435.71 million lbs. At these deposition levels, loads to tidal waters of the Bay are estimated by the model to be 188.75 million lbs, again, assuming the same land conditions as the baseline. All in all for the 2007 air indicator status, a 8.41 million lb. reduction in nitrogen deposition from 1985 translates to a 1.18 million lb. reduction in loads to the Bay from 1985.

The air indicator goal is to reach the Bay watershed-wide cap load of 175 million lbs. TN/year. Planned reductions to meet this cap load include benefits from air programs in jurisdictional Tributary Strategies as well as an 8 million lb. load reduction that EPA has committed to. The load reduction goal from the 1985 baseline from air programs is 14.78 million lbs. of nitrogen. The 2007 air indicator status would therefore be 1.18/14.78 or 8.0% of the air goal achieved.

Yes. Relational databases and spreadsheet analyses are used to calculate point source discharges as well as assimilate nonpoint source BMP data and watershed conditions (i.e., land uses, animal populations and nutrient applications to land, septic) to formats needed for watershed model input decks. The Chesapeake Bay Program Phase 4.3 Watershed Model is, in turn, employed to integrate the point and nonpoint source data and assess edge-of-stream loads and loads delivered to the Chesapeake Bay’s tidal waters.

(24) Are the computations widely accepted as scientifically sound?
Yes. See section 21 under “Data Analysis and Interpretation”

(25) Have appropriate statistical methods been used to generalize or portray data beyond the time or spatial locations where measurements were made (e.g., statistical survey inference, no generalization is possible)? Yes.

Agriculture, Urban/Suburban and Septic, Air:
 Nonpoint source BMP data may be distributed spatially and among relevant land use types according to methods established by the Bay Program Tributary Strategy Workgroup if information tracked and reported by jurisdictions is not of sufficient detail to generate Watershed Model input decks. Refer to:
o Quality Assurance Project Plan (QAPP) “Standard Operating Procedures for Managing Nonpoint Source Data – Chesapeake Bay Program” on file for the EPA grant (contact: Quality Assurance Coordinator, Mary Ellen Ley, mley@chesapeakebay.net).
 Indicator goals for nonpoint sources are rooted in projected watershed conditions (landuses, animal and human populations, septic, and atmospheric deposition) for the year 2010 as assessed by jurisdictional representatives or following Tributary Strategy Workgroup forecast protocols using statistical analyses.
 As noted in Section 22, the status for the air indicator includes a projection of 1985-2005 calibration deposition data to 2007. The deposition information is, in turn, used as inputs to the Watershed Model to assess a response in loads to the tidal Bay. These loading figures are the elements of the indicator.

(26) Are there established reference points, thresholds or ranges of values for this indicator that unambiguously reflect the desired state of the environment? (health/stressors only)

F. Data Quality

Please provide appropriate references and location of documentation if hard to find.)

(27) Were the data collected according to an EPA-approved Quality Assurance Plan? If no, complete questions 28a – 28d:

Jurisdictions providing point source effluent data and nonpoint source BMP data to the Bay Program office have supplied documentation of their quality assurance and quality control policies, procedures, and specifications in the form of Quality Assurance Management Plans and Quality Assurance Project Plans. Jurisdictional documentation can be obtained by contacting the Quality Assurance Coordinator, Mary Ellen Ley,mley@chesapeakebay.net).

(28a) Is the sampling design and/or monitoring plan and/or tracking system used to collect the data over time and space based on sound scientific principles?

(30) Were the sampling and analysis methods performed consistently throughout the data record?

Wastewater:
 Monitored discharge data were generated from the EPA-approved standard sampling and analysis methods and documented in the Data Monthly Reports from facilities to jurisdictions.
 Discharge data back to the earlier years of the record are inadequate for many regions in the Bay watershed; however, the 1985 baseline is consistent throughout the indicator record.
 Facilities have been added to the point source database over the years, not necessarily because they physically went on line, but because they were previously untracked. In addition, facilities have been turned inactive in the point source database over time because they went off line or combined with other facilities as new plants.
 Protocols of calculating discharges from measured or estimated flows and effluent concentrations have been adjusted throughout the data record to better reflect actual end-of-pipe loads.
 Jurisdictional Tributary Strategies may not be final so the goals could be adjusted in the future as jurisdictions update implementation plans that better reflect projected point source discharges.

Agriculture, Urban/Suburban and Septic, Air:
 For some nonpoint source BMPs and some jurisdictions, implementation levels reported for annual model assessments have increased or decreased significantly over the data record, not necessarily because of on-the-ground implementation, but because of the establishment of or changes to tracking mechanisms or because new or revised resource assessments were performed.
 Adjustments to the methods of crediting nonpoint source BMP implementation have occurred over the period of the data record to better reflect on-the-ground conditions. For example, significant changes in the peer-reviewed effectiveness of several agricultural BMPs occurred between the 2001 and 2002 reporting period. In addition, model adjustments were made between the 1985 and 2000 scenarios universally decreasing urban nitrogen loads by 15% and urban phosphorus loads by 30%.
 Tributary Strategies are dynamic so the goals can be adjusted in the future as jurisdictions update implementation plans that better reflect projected nonpoint source implementation levels.

(31) If datasets from two or more agencies are merged, are their sampling designs and methods comparable?

Wastewater:
 Point source data sets from seven jurisdictions are merged at the Chesapeake Bay Program office. Continual peer-review of the thoroughness of discharge data and methods of managing the information by the Wastewater Treatment Workgroup promotes consistency and completeness of calculated end-of-pipe loads among the jurisdictions.

Agriculture, Urban/Suburban and Septic, Air:
 Means of collecting and methods of analyzing nonpoint source BMP data vary among jurisdictions depending on the sophistication of their tracking mechanisms and resources devoted to managing the information. Jurisdictions providing nonpoint source BMP data to the Bay Program office have supplied documentation of their quality assurance and quality control policies, procedures, and specifications in the form of Quality Assurance Management Plans and Quality Assurance Project Plans. This documentation can be obtained by contacting the Quality Assurance Coordinator, Mary Ellen Ley, mley@chesapeakebay.net).
 Nonpoint source BMP implementation data from seven jurisdictions are merged at the Chesapeake Bay Program office. Continual peer-review of the data and methods of applying the data by Nutrient Subcommittee workgroups promotes consistency and completeness among the jurisdictions. To improve uniformity in reporting nonpoint source BMPs among jurisdictions, summary and detailed information about the practices and reporting criteria are accessible on the Bay Program Tributary Strategy Tools web site (http://www.chesapeakebay.net/tributarystrategy_tools.aspx) including the following:

(32) Are uncertainty measurements or estimates available for the indicator and/or the underlying data set? No

(33) Do the uncertainty and variability impact the conclusions that can be inferred from the data and the utility of the indicator? No. Significant uncertainty and variability could be traced. Causes of the uncertainty and variability could be documented to limit its impact on the conclusion.

The Chesapeake Bay Program Watershed Model, employed to integrate point source technology controls and a large array of nonpoint source BMPs, is best utilized when making comparisons among scenarios. For the Reducing Pollution indicators, these comparisons are among the 1985 baseline, the yearly model assessments of loads, the Tributary Strategy goals for individual sources, and cap load allocations for the summary indicator.

By presenting trends and status at the large scale of the 64,000 square mile watershed over a 20-year period, yearly changes in data tracking mechanisms by particular jurisdictions and changes in methods of data analysis for particular point and nonpoint source BMPs are somewhat masked.

The indicators are designed 1) to depict, generally, the degree of progress over the long term toward the implementation goals and 2) to clearly identify pollutant sources where gaps are large and to what extent. The Reducing Pollution indicators connect efforts (point and nonpoint source controls) with results (loading reductions and subsequently, water quality and habitat health).

(34) Are there noteworthy limitations or gaps in the data record? Please explain. Yes

 As noted in section 22, nonpoint source BMP implementation data were not reported consistently and for all watershed jurisdictions for the period 1986-1999. Therefore, the 1986-1999 levels of the Agriculture and Urban/Suburban and Septic indicators are a linear progression between the 1985 baseline and the year 2000. For the Air indicator, data is used for the years 1985, 1996, 2001, and 2005-2007 inclusive. Other years within the air indicator trend period are interpolations of the data.

G. Additional Information

(optional)

(35) Please provide any other information about this indicator you believe is necessary to aid communication and prevent any potential misrepresentation.